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Denne Ph.D. afhandling omfatter fundamentale betragtninger omkring topologier, algoritmer, implementeringer, metoder etc., der kan indg˚a i næste generation af aktive kontrol systemer. Specifikt foresl˚as der en variant af feedforward kontrol refereret til som indesluttet feedforward aktiv kontrol forkortet IFFAK. I denne topologi indg˚ar et sæt reference sensorer, der er positioneret p˚a en overflade, der fuldt ud indeslutter de ønskede stille-zoner, hvori et sæt performance sensorer monitorerer den opn˚aede støjreduktion. Denne indesluttet-feedforward aktiv kontrol (IFFAK) topologi er indlejret i et mange-input-mange-output (MIMO) system, der omfatter b˚ade feedforward og feedback kontrol. Det totale system er refereret til som et hybrid MIMO indesluttetfeedforward FBS (HMIMOIFFFBS). Undersøgelsen af et komplekst multi-kanals aktiv støjreduktion (ASR) system med hybrid feedforward og feedback topologier er motiveret ud fra krav om høj aktiv støjdæmpning i ekstreme støjmiljøer, som f.eks. opleves ombord p˚a luftb˚arne militære platforme. Støjoptagelser erhvervet ombord p˚a s˚adanne fartøjer afslører lydtryk, der ofte overstiger 140 dB re. 20 μPa. Endvidere udviser disse støjsignaler store tidslige s˚avel som spatiale variationer. Naturlige begrænsninger i feedback baserede aktiv kontrol (AK) systemer som typisk anvendes i moderne ASR støjværn, hvor modstøjssignalet notorisk er forsinket i forhold til den primære forstyrrelse, sætter en øvre grænse for, hvor stor en aktiv dæmpning, der kan opn˚aes. S˚aledes, hersker der i krævende militære applikationer et krav om nye mere avancerede og effektive ASR løsninger. Den opn˚aelige ASR i et FFS er i stor udstrækning bestemt af kohærensen mellem sættet af reference sensorer og sættet af fejl- eller performance sensorer. S˚aledes omfatter denne afhandling en del kohærensundersøgelser baseret p˚a diffustfeltsm˚alinger i et støjkammer samt m˚alinger, der er foretaget i en CH-47D Chinook helikopter. Fra disse kohærensanalyser kan det konkluderes, at IFFAK systemet anvendt p˚a pilothjælme giver mulighed for ca. 25 dB støjreduktion ved 100 Hz faldende til ca. 10 dB dæmpning ved 900 Hz. Endvidere, er der ikke nogen umiddelbare tegn p˚a en mætning med stigende antal reference sensorer. S˚aledes vil et større antal reference sensor forventeligt kunne øge den øvre ASR frekvensgrænse for systemet, der bestemmes af den rumlige samplingstæthed. I hybridsystemet indg˚ar der b˚ade et kontinuerlig-tids FBS og et diskret-tids FBS. Disse vil bidrage med yderligere støjreduktion primært overfor bredb˚andet støj henholdsvis overfor periodiske signaler. Tidsforsinkelser udgør en anden bestemmende faktor for den opn˚aelige effekt i et FFS design, men specielt i et FBS design, eftersom fysiske systemer altid opererer kausalt. For at vurdere størrelsesordenen af det tidsforspring som hver reference sensor giver i forhold til hver fejlsensor i det foresl˚aede IFFAK system indføres en størrelse, der betegnes som den spatialt-vægtet middeltidsgevinst. Der eksisterer imidlertid et problem, n˚ar man forsøger at modellere et fysisk system med en endelig rummelig udstrækning og hvor der s˚aledes ikke er nogen indlysende input-output definition med et endeligt-element multi-kanals system. Som regel eksisterer der ikke nogen unik overføringsfunktion eftersom systemet ikke bliver punktvist stimuleret, men derimod stimuleret xii over et areal som for eksempel under diffustfelts belysning. En ny akustisk signalbehandlingsmetode, der betegnes som samlet kanal residual spektral analyse (SKRSA) er udviklet. Denne metode benyttes til ekstraktion af fælles signal information fra forskellige observationspunkter i rummet. Ideen er at separere hvert spektrum i et kohærent spektrum og et residual spektrum. Indholdet i det kohærente spektrum kan opn˚aes som en linear kombination af spektrene fra de andre kanaler, hvorimod indholdet af det residuale spektrum er unikt for den p˚agældende kanal. I et specifikt eksempel, belyses et system best˚aende af et sæt reference sensorer monteret p˚a en Gentex HGU-55/P hjælm, der igen er p˚amonteret en hoved og torso simulator med et diffust lydfelt. Under anvendelse af SKRSA metoden estimeres den spatialt-vægtet middeltidsgevinst til at være i størrelsesorden 800-900μs. Afhandlingen omfatter ogs˚a en detaljeret beskrivelse af en ny id´e til en beregningsmæssig effektiv implementering af et multi-kanals system, hvor b˚ade de adaptive filtre, der indg˚ar i den aktive kontrol s˚avel som de adaptive filtre, der indg˚ar til modellering af systemoverføringsfunktionerne kan antage individuelle længder. En ny og mere generel variant af APA algoritmen er udviklet. Denne adaptive filter algoritme inkluderer parametre for b˚ade wægt-styret og kontrol-effekt-styret lækage, adaptiv tap-vægte regulering s˚avel som numerisk regulering og betegnes MC-αγΠ-APA. En simplificering af denne algoritme, fører til MC-αγΠ-NLMS algoritmen, der er en udbygget variant af NLMS algoritmen. Systemets evne til off-line simultant at kunne identificere et complex system best˚aende af ialt 28 enkelt systemgrene bliver demonstreret. Forskellig adaptive filtre samt parametering heraf bliver udforsket. Et nyt og generelt multi-hastigheds systemkoncept for aktiv kontrol er udviklet. Specifikt implementeres og testes et system, hvor der i alt samples med tre forskellige hastigheder. P˚a multi-hastighedsniveau 0 benyttes en meget høj samplingsfrekvens med henblik p˚a at reducere forsinkelser i konverteringstrinene, der indg˚ar i de sekundære grene. Den ikke adaptive kontrol udføres p˚a det lavere multi-hastigheds niveau 1. Herved tilsikres et kompromis imellem forsinkelser til afgivelse af modstøjssignaler og krav til en endelig system b˚andbredde. Sluttelig foreg˚ar den adaptive kontrol ved det lavere multi-hastigheds niveau 2. Herved begrænses den ofte beregningsmæssige tunge adaptive filter opdatering til en s˚a lav samplingsfrekvens som muligt. I et specifikt eksempel demonstreres, at en beregningsmæssig besparelse p˚a ca. 40% kan opn˚as under opretholdelse af samme ASR ved nedsampling fra multi-hastighedsniveau 1 p˚a 24 kHz til multi-hastighedsniveau 2 p˚a 3 kHz. Det er en almindelig ingeniørpraksis at foretage en antagelse om Gaussisk fordelte signaler. Imidlertid, er mange fænomener i dagligdagen bedst modelleret med s˚akaldte alfa-stabile fordelings funktioner. Dette gælder ogs˚a for støjsignaler, der ønskes undertrykt ved hjælp af et aktivt støjdæmpningssystem. Afhandlingen indholder en kort teknisk beskrivelse af de stabile fordelingsfunktioner samt adaptive filter algoritmer for disse type signaler. Store dele af HMIMOIFFFB systemet samt de udviklede metoder og algoritmer er implementeret i et realtids miljø, der inkluderer en signal processor. I første omgang vil disse blive aftestet p˚a en til form˚alet designet aktive kontrol testenhed. ; This Ph.D. thesis includes fundamental considerations about topologies, algorithms, implementations, methods etc., that can enter in the next generation of active control (AC) systems. Specifically, a new variant of feedforward control referred to as confined feedforward active control (CFFAC) is proposed. This topology is constituted from a set of reference sensors that are positioned on a surface that completely confines the desired zones of quite. A set of performance sensors monitors the achieved noise reduction. This CFFAC topology in turn is embedded in a multiple-input and multiple-output (MIMO) system that facilitates both feedforward and feedback control. The general system is then referred to as hybrid MIMO confined-feedforward feedback (HMIMOCFFFB) active noise reduction (ANR) system. The investigation of a multi-channel ANR system with hybrid feedforward and feedback topologies is motivated by requirements of high ANR attenuation in extreme noise environments as typically experienced onboard airborne military platforms. Noise recordings acquired on such platforms reveal very high sound pressure levels often exceeding 140 dB re. 20 μPa. Moreover, these noise signals exhibit large temporal as well as spatial variations. Inherent limitations are related to the use of stand-alone feedback AC implementation commonly applied in modern ANR headset. In such systems the anti-noise signal is notoriously behind the primary disturbance in time. Accordingly, in demanding military applications requirements on more advanced and effective ANR system designs prevail. The achievable ANR performance in a feedforward system (FFS) is to a large extent determined by the degree of coherence between the set of reference sensors and the set of error sensors (or performance sensors). Accordingly, this thesis includes a number of coherence analysis that are based on diffuse sound field measurements in a reverberant chamber and measurements conducted onboard a CH-47D Chinook helicopter. From these coherence analysis it can be concluded that the CFFAC system with 10 reference sensors applied to pilot helmets potentially provides approximately 25 dB noise reduction at 100 Hz decreasing to approximately 10 dB attenuation at 900 Hz. Moreover, there is no apparent sign of saturation of the noise reduction with an increasing number of reference sensors. Accordingly, by using more reference sensors the spatial sampling rate is increased which in turn most likely also will lead to an increased ANR bandwidth. The hybrid system is also constituted from a continuous-time feedback system (FBS) and a discrete-time FBS. The continuous-time FBS is primarily responsible for additional broadband noise reduction, whereas the discrete-time FBS primarily is responsible for the attenuation of periodic signals. Owing to the requirement on causal operation of a physical AC system time delays will also to a large extent determine the achievable performance in FFS design and in particular in FBS design. A quantity referred to as the spatially-weighted-averaged acquisition lead time is introduced to represent the averaged time-advance obtained by each reference sensor relative to each performance sensor involved in the proposed CFFAC system. A problem exist when one attempts to model a physical spatially distributed system with no obvious input and output channel definition by a finite lumped-elements multi-channel system. Usually, no unique transfer function x exist as the system is not point-wise excited, but excited over an area as in the case of diffuse sound field illumination. A new method for acoustical signal processing that is referred to as joint-channel residual spectral analysis (JCRSA) is developed. The JCRSA method is used for the extraction of joint signal information from different observation positions in space. The idea is to separate each spectrum in a coherent spectrum and a residual spectrum. The contents of the coherent spectrum can be obtained from a linear superposition of the other signals, whereas the residual spectrum bears information that is unique to each specific channel. In a specific example a system consisting of 10 reference sensors flush-mounted on a Gentex HGU-55/P helmet that in turn is mounted on a head and torso simulator (HATS), is exposed to diffuse sound field illumination. By applying the JCRSA method the spatially-weighted-averaged acquisition lead times provided by the reference sensors relative to the performance sensors are estimated to be as much as 800-900μs. The thesis also includes a detailed description of a new idea for a computational efficient implementation of a multi-channel system in which the adaptive filters for adaptive control as well as the adaptive filters used for plant modeling are allowing to take different lengths. A new and more general variant of the affine projection algorithm has been developed. This adaptive filter algorithm that is denoted by multiple-channel-αγΠ-affine projection algorithm includes parameters for both weight-driven and control-effort-driven leakage, adaptive tap-weight regularization as well as numerical regularization. A simplification of this algorithm leads to the MC-αγΠ-NLMS algorithm that is an extended variant of the NLMS algorithm. Off-line simultaneous system identification capabilities of a complex system involving a total 4 secondary paths, 20 feedback paths and 4 control-performance paths is demonstrated. Different adaptive filters and parameterizations hereof are examined. A novel and general multi-rate adaptive filter for adaptive AC has been developed. Specifically, a system involving 3 different sampling rates has been implemented and the results hereof are presented. In this multi-rate system conversion take place at highly oversampled rates in order to reduce the delays in the secondary paths. The non-adaptive control is performed at a somewhat lower rate. Hereby, a compromise between delays related to the generation of the anti-noise signal and the computational load involved is ensured. Finally, the adaptive control that might be computational intensive takes place at an even slower sampling rate hereby relaxing the requirements on a high bandwidth. It is demonstrated that computational savings as high as 40% can be achieved in a 192, 24, 3 kHz triple-rate system as compared with a 24 kHz single-rate system without sacrificing the ANR performance. It is common engineering practice to apply an assumption of Gaussian distributed signals. However, many phenomena encountered in daily life fall into a generalization of the normal distribution that is referred to as α-stable distributions. Noise sources encountered in the domain of AC are sometimes best fitted to the family of α-stable distributions. This thesis includes a brief technical introduction to the stable distributions and description of the adaptive filter that can be used for AC. Large parts of the HMIMOCFFFB system including the developed methods and algorithms have been implemented in a real-time environment (RTE) that includes a signal processor. Test on the helmet system will continue and a dedicated reference test unit (RTU) for AC is currently being designed.

On July 13(th) 2010, Lazlo Andor (Commissioner for Employment, Social Affairs and Inclusion) declared that active ageing could make the baby-boomers generation a part of the solution of the demographic problem, instead of identifying with it. This is the reason why the "Europe 2020" strategy draws the attention to the necessity of ensuring that the elderly will remain healthy and active for as long as possible. The purpose of this article is to define the exact concept of "active ageing", its content, as well as some beneficial tips by applying innovative programs in order to promote it in the European Union. Reading the published papers the impression is that despite the increasing number of the elderly in Europe, the potential of an active life while ageing can be beneficial in many ways for the society. It is required that the local and regional authorities create the appropriate conditions for participation, while making thoughtful use of the European funding programs.

This article belongs to the Section Material Sciences. ; Definition: Active edible packaging is a food packaging made of comestible bioproducts and active compounds that interacts with the food. The bioproducts, usually biopolymers, must be recognized as safe and with characteristics to be consumed by humans—comestible—and not toxic and capable of carrying an active compound, like anti-browning agents, colorants, flavors, nutrients, antimicrobial and/or antioxidant compounds, in order to extend the product shelf-life, reduce contamination and maintain or even enhance the nutritional value. ; This work was supported by UIDB/04077/2020 and UIDB/00211/2020 with funding from FCT/MCTES. This research was also supported by the PANACEA project that has received funding from the European Union's Horizon 2020 Research and Innovation program under Grant Agreement 773501. ; info:eu-repo/semantics/publishedVersion

This contribution about the Netherlands to the special issue [or: section] on volunteering and civic action focuses on changes in public understanding and policy perspectives. Developments since the second half of the nineteenth century show shifting emphases on active membership (based on associational life and typical of the phenomenon of pillarization'), active citizenship (based more on an individual sense of responsibility and more or less political in nature) and unpaid work (volunteering as a gift to society and other people). Government policy over the last two decades has focused heavily on reponsibilization' of citizens, both as regards providing help to others when they need it (unpaid work/informal care) and in terms of their relationship with the society in which they live (active citizenship). We expand further on the recent notion of the do-democracy' as a populist and anti-political way of doing things together on a small scale instead of engaging in democratic controversies and trying to get a grip on big issues.

• Banov's food inspectors continue to be active, with the aim of safeguarding the health of the military and naval forces stationed in and around Charleston ; Newspaper article ; 10

This article discusses active qualitative evaluation and modern sociotechnical design as parts of an approach for the evaluation of organizational change. 'Intervention in interactions' is the most important similarity between these parts when considering the evaluation of organizational change. The two parts are discussed in terms of their theoretical core elements, practical consequences for research and dilemmas. Because, in practice, intervening in a changing organization is always accompanied by some important paradoxes, the different parts of the approach are presented as supplementary in practical evaluation of organizational change. The leitmotif on the basis of the case of the Royal Netherlands Military Academy here is that a paradoxical situation such as intervening in a changing organization needs a paradoxical intervention strategy.

17 USC 105 interim-entered record; under review. ; The article of record as published may be found at https://cimsec.org/active-learning-for-active-minds-a-conversation-with-learning-leaders/ ; U.S. Government affiliation is unstated in article text.

The concept of &lsquo ; Active Aging&rsquo ; emerged in the 1990s, reflecting a growing emphasis on the relationships between health, participation, aging, and independence. The concept focuses on encouraging the participation of older adults in society and it recognizes the competence and knowledge that older people possess. The Active Aging discourse developed as a broad political response to demographic aging, one which promotes a cultural shift in what &lsquo ; old age&rsquo ; may mean, by providing older people with new roles. The initiative &ldquo ; Age-Friendly Cities and Communities&rdquo ; which was launched by the WHO in 2007, was developed with the aim of applying this paradigm into practice at the local level. Its purpose was to promote a movement of citizen participation where older people have a leading role as generators of well-being, and tackling the barriers of Active Aging. This paper provides a theoretical reflection concerning the development of the concept of Active Aging and how this has led to new ways of active citizenship in later life. New generations of older people demand a space where they can develop and contribute to society, regardless of their age. The aging of the population poses challenges and opportunities, which we can and must take advantage of in order to build a better and more egalitarian society, one that recognizes the value of diversity.

The paper argues that a comprehensive activation strategy is called for – in both unemployment and disability insurance – to minimize the conflict between income insurance and work incentives and to prevent the economic crisis from causing a long-lasting decline in labor force participation. A review of recent empirical evidence, particularly from the Scandinavian countries indicates that mild activation requirements effectively counteract moral hazard problems in social insurance. The paper also argues that the distinction between unemployment and disability is blurred, and that both temporary and permanent disability insurance programs should be designed to encourage and support the use of remaining (partial) work capacity.

"Best recent books which the history and government of Illinois": p. 56. ; Mode of access: Internet.

International audience ; In post-apartheid South Africa, efforts to encourage practices of citizenship and new citizens who will act in ways that support communities and the nation are promoted by government policies and networks of international organizations, civil society groups, and NGOs. In this paper, we analyse the pedagogy of citizenship that is common in these efforts and the role of 'active citizenship' within it. Relying on interviews with leaders of NGOs and activist groups and on participatory research with six organizations, we examine the ways in which different meanings and

International audience ; In post-apartheid South Africa, efforts to encourage practices of citizenship and new citizens who will act in ways that support communities and the nation are promoted by government policies and networks of international organizations, civil society groups, and NGOs. In this paper, we analyse the pedagogy of citizenship that is common in these efforts and the role of 'active citizenship' within it. Relying on interviews with leaders of NGOs and activist groups and on participatory research with six organizations, we examine the ways in which different meanings and

Ageing takes place in Finland some 15 years earlier than in other European countries. The central actors in implementing active ageing policies are ministries that have been co-operating with each other. Active ageing policy in Finland has some of the advantages of networking in a small country, and also in the anticipation of the decrease in the share of the active population. First, all three central ministries, the Ministry of Social Affairs and Health, the Ministry of Labour and the Ministry of Education co-operate with each other. The success of various ageing programmes is largely based on this. In other countries, ministries usually have independent policies. Second, social partners include representatives of employers' and employees' organisations, as the tradition of tripartite thinking is strong in Finland. Third, research organisations support the research. For example, in the Finnish Institute of Occupational Health ageing studies began as early as 1981. Fourth, active ageing policies also focus on firm-level issues in addition to measures implemented at the individual and society levels. Firms have a clear incentive to prevent pensioners on disability emerging, since firms themselves have to pay a large part of the eventual pension expenses. There are, however, also major setbacks. Active ageing programmes such as the Ageing Programme and the Well-Being at Work Programme have been implemented in Finland for a fixed time period. There is a threat that much of the networking is lost after the programmes terminate. The cooperation between ministries may also diminish in the future programmes. The major problem in Finland that is not solved by any well being programmes is that the routes to exit from work are too generous. A new work life reform to renew the values of work is also called for. Finally, the integration of worklife and family life is considered an important issue, but issues related to active non-work time are seldom considered. An example of active time use that is ignored is household work. Household work is on average one third of the labour income for men and two-thirds of the labour income for women at age 50-64. Finally, the state of senior citizen policy is not very good in Finland. Private organisations of pensioners are relatively inactive. – Retirement ; Ageing Policy ; Demographic Trends ; Väestön ikääntyminen alkaa Suomessa noin 15 vuotta aikaisemmin kuin muissa Euroopan maissa. Keskeiset toimijat ikääntymisohjelmissa ovat ministeriöt, jotka ovat toimineet yhteistyössä. Yhteistyötä on edesauttanut verkostojen luominen, mikä voi olla helpompaa pienessä maassa. Yksi esimerkki tästä on sosiaali- ja terveysministeriön, työministeriön ja opetusministeriön yhteistyö, johon eri aktiiviseen ikääntymiseen liittyvien ohjelmien onnistuminen on perustunut. Eri työmarkkinaosapuolet ovat myös osallistuneet aktiivisesti toimintaan, joka on siten perustunut pitkälle kolmikanta-ajatteluun. Tutkimuslaitokset ovat myös tukeneet tutkimusta. Esimerkkinä tästä on Työterveyslaitoksen ikääntymistutkimus, joka on saanut alkunsa jo vuonna 1981. Viimeinen tärkeä tekijä aktiiviseen ikääntymiseen tähtäävien ohjelmien onnistumiselle on yritystason toiminta. Muista maista poiketen yrityksillä on selvä kannustin välttää työkyvyttömyyttä, koska yritykset kantavat suuren osan työttömyyseläkkeiden kustannuksista. Aktiivisen ikääntymisen toimenpiteissä on kuitenkin myös omat puutteensa. Ensinnäkin ikääntymisohjelma ja työssä jaksamisen ohjelma on asetettu määräajaksi. Uhkana on, että verkosto ei jatka toimintaansa ohjelmakauden loputtua. On myös mahdollista, että ministeriöiden välinen yhteistyö ei ole riittävää tai vähenee tulevaisuudessa. Aktiivisen ikääntymisen tavoitteiden toteuttaminen edellyttää myös työmaailmaan liittyvän arvomaailman uudistamista, missä ei olla edistytty riittävästi. Yksi ongelma on myös se, että työn ja perhe-elämän yhteensovittaminen koetaan kyllä tärkeäksi, mutta kuitenkin toiminta rajoittuu yleensä työssä jaksamiseen eikä aktiivisuuteen myös työajan ulkopuolella. Yksi esimerkki ajankäytöstä, johon ei panna paljoakaan painoa, on kotitaloustyö. Kuitenkin esimerkiksi 50-64 -vuotiailla kotitaloustyön arvon on noin kolmasosa palkkatyön arvosta miehillä ja kaksi kolmasosaa palkkatyön arvosta naisilla. Voidaan myös todeta, että eläkeläisjärjestöjen aktiivisuus on varsin vähäistä.

International audience ; The long-term outlook for global ocean abundance of living marine resources is uncertain. Times have changed quickly. Some States have reacted to the decline in marine resources with two generic strategies. First States have been designating a variety of marine protected areas in part to respond to SDG target 14.5 to «conserve at least 10% of coastal and marine areas». Second, States have been investing in better monitoring and enforcement programs to address illegal fishing. These solutions may ameliorate certain human pressures on ecosystems, but do not directly contribute to the enhancement of marine ecological values. Active marine restoration is the coordinated efforts by individuals or groups to revive the structures and functions of ecological systems. This might include targeted efforts to revive habitat that is damaged through active planting of seagrasses or grafting of coral reefs. This might include releasing fish or other marine animals into an area to increase the breeding population. Some States are engaged in active marine restoration efforts. But the number of States undertaking such projects is limited.This chapter offers three political proposals with legal implications to further active marine restoration and improve state performance under existing duties to restore marine stocks and ecosystems. First, States need to enhance their existing marine scientific research cooperation to improve measures that support «active marine restoration» including incorporating new types of knowledge into assisting in ecosystem recovery. Second active marine restoration focused on accelerating restoration efforts should be mainstreamed as an international «blue economy » development strategy. Finally, given that oceans have permeable geopolitical boundaries, effective active marine restoration may require a new institutional approach that is not state-based but guardian-based. If an Ocean Guardian Council was to convene and be given powers by States to protect ocean interests ...

• Claude R. Porter, Democratic candidate for Governor, visits Des Moines• Porter will give few speeches due to influenza epidemic• Porter's general platform outlined in article ; Newspaper article ; 5